Current RMA Instruments
| Reasonable Hypothesis SOP | 74 of 2020 |
| Balance of Probabilities SOP | 75 of 2020 |
Changes from previous Instruments
ICD Coding
- ICD-9-CM Codes: 322.9
- ICD-10-AM Codes: G03.9
Brief description
This is a rare condition involving chronic inflammation of one of the membranes that surrounds the spinal cord. It can result in debilitating back pain and neurological deficits.
Confirming the diagnosis
This condition needs to be positively differentiated from other causes of (particularly low) back pain. The diagnosis requires: evidence from imaging (MRI scan) or at operation of inflammation of the arachnoid membrane of the spinal cord; and, clinical (neurological) manifestations that are consistent with the observed pathology.
The relevant medical specialist is a spinal/neurosurgeon or a pain management specialist.
Additional diagnoses covered by SOP
- Arachnoiditis ossificans
- Chronic spinal arachnoiditis
- Lumbar adhesive arachnoiditis
Conditions excluded from SOP
- Arachnoiditis of the brain or cranial nerves
Clinical onset
Clinical onset will follow after a triggering event such as severe trauma, surgery or an injection to the affected area of the spine. The typical presentation will be the onset of (new) severe pain at the site. This may develop anywhere from shortly after to some years later.
Clinical worsening
Pain tends to be severe and debilitating from early in the disease course and to be fairly stable thereafter. No curative treatment is available. Therapy is aimed at relieving pain (while minimising reliance on addictive analgesic medications).